Subtract 81/18 from 20/10
1st number: 2 0/10, 2nd number: 4 9/18
20/10 - 81/18 is -5/2.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 18 is 90
Next, find the equivalent fraction of both fractional numbers with denominator 90 - For the 1st fraction, since 10 × 9 = 90,
20/10 = 20 × 9/10 × 9 = 180/90 - Likewise, for the 2nd fraction, since 18 × 5 = 90,
81/18 = 81 × 5/18 × 5 = 405/90 - Subtract the two like fractions:
180/90 - 405/90 = 180 - 405/90 = -225/90 - After reducing the fraction, the answer is -5/2
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/10-81/18 20/10-81/36 60/10-81/18 20/30-81/18 20/10-81/54 20/50-81/18 20/10-81/90 20/70-81/18